Venue Materials - duplicate dos not work

When i duplicate a material in the Venue Material Menu, i can't find it when i open up this menu later. My new material is not recorded. I dont have any error message, everything seems to be OK.
It may be important to know that i run under Windows Vista.

Copying a material creates an .xml file and a preview image in your project's folder. Vista is very protective about anything that happens in your program files (x86) folder, so if that's where BTB is, you'll need to configure the .exe to run with Administrator privileges.

BTB is actually in the Program Files folder. I have the same trouble even when i run it as administrator. In fact, i realise that i can't even modify an existing material, the Scale and Offset options does work, but not the Angle.

I have installed BTB (trial licence) on a XP PC to see what happen in this menu: Duplicate still not working, neither the angle option.
So to resume, i have the same problems whether i am running Vista or XP. Am i the only one ?
So there is no chance to modify the angle of a texture unless i add a new texture in a expansion pack...

Yes, it does but it's not track textures I want to rotate. It's terain texs.
To get rotated textures I can either add bits and pieces of track in the infield and try to line up terain texture to it, or use walls as ground and line up terain to that. But I'd rather just set up some of same texture at various rotations than have to have the same physical texure repeated several times at different angles. This uses up precious memory reapeating the same texture. If rotate worked on terain, the same texture could be reused.